Použijte ||
pro zřetězení v oracle
SELECT A.*,
K1.AD || K1.SYD as CONTACT,
KR.AD KURUM,
K2.AD SUPERVISORAD,
K2.SYD SUPERVISORSOYAD,
K3.AD REQUIRERAD,
K3.SYD REQUIRERSOYAD
FROM
TD_ACTIVITY A,
KK_KS K1,
KK_KS K2,
KK_KS K3,
KK_KR KR
WHERE A.INS_CONTACT_PERSON = K1.ID
AND A.SUPERVISOR = K2.ID
AND A.REQUIRERID = K3.ID
AND A.INSTITUTIONID = KR.ID